This invention relates to brake linings, and in particular to brake linings made by a novel method of manufacture.
In U.S. Pat. No. 4,656,203 there is described a friction material having a high void content, the preform for which is made by a slurry technique, and in U.S. Pat. No. 4,775,705, which is a continuation in part of the former patent, there is described the manufacture of brake pads containing high proportions of fibre and a higher void content than usual, again the method of making a preform being a slurry technique.
We have now found that in the manufacture of brake linings the slurry technique as described hitherto produced unsatisfactory results with uneven distribution of ingredients because of the curved profile of the lining which is needed. It is an alternative to produce a flat sheet of material by the slurry technique and then mold this to the desired curved shape but this adds an additional process step, which is expensive.
Thus it is an object of this invention to provide a method of making brake linings by means of a slurry preforming technique.
It is another object of the invention to provide a novel brake lining which is produced from a preform made by the aforementioned slurry preforming technique.